The Biostatistics core will continue to provide data entry and data management support as well as statistical and epidemiological collaboration for the six UW CRC projects during the coming year and to the four new CRC projects described in the current application. In addition the Biostatistics core will continue to support trainees and STDCRC New Investigator award recipients. Specifically, the Biostatistics Core will I) provide statistical and epidemiological collaboration and consultation on study design; forms design, evaluation and pretesting; and data analysis; 2) develop and maintain a database linking the clinical and laboratory results for the proposed studies; 3) provide data entry services; 4) collaborate in the writing of manuscripts, paying special attention to accurate descriptions of study design, data analysis and interpretation of results; 5) develop, adapt and/or implement new or novel statistical methods as needed; and 6) maintain computing facilities which are available (both on site and by remote login) to any investigator. In addition, the core will collaborate with the Biostatistical core of the NIH-funded UW Center for AIDS Research to promote interactions and collaboration among biostatisticians and epidemiologists involved in federally funded STD and HIV-related research at the UW.